//========================================================================
// GLFW 3.3 - www.glfw.org
//------------------------------------------------------------------------
// Copyright (c) 2002-2006 Marcus Geelnard
// Copyright (c) 2006-2018 Camilla Löwy <elmindreda@glfw.org>
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
//    claim that you wrote the original software. If you use this software
//    in a product, an acknowledgment in the product documentation would
//    be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such, and must not
//    be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source
//    distribution.
//
//========================================================================
// Please use C89 style variable declarations in this file because VS 2010
//========================================================================

#include "internal.h"
#include "mappings.h"

#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <assert.h>

// The global variables below comprise all mutable global data in GLFW
//
// Any other global variable is a bug

// Global state shared between compilation units of GLFW
//
_GLFWlibrary _glfw = {GLFW_FALSE};

// These are outside of _glfw so they can be used before initialization and
// after termination
//
static _GLFWerror _glfwMainThreadError;
static GLFWerrorfun _glfwErrorCallback;
static _GLFWinitconfig _glfwInitHints =
    {
        GLFW_TRUE, // hat buttons
        {
            GLFW_TRUE, // macOS menu bar
            GLFW_TRUE // macOS bundle chdir
        }};

// Terminate the library
//
static void terminate(void) {
  int i;

  memset(&_glfw.callbacks, 0, sizeof(_glfw.callbacks));

  while (_glfw.windowListHead)
    glfwDestroyWindow((GLFWwindow*)_glfw.windowListHead);

  while (_glfw.cursorListHead)
    glfwDestroyCursor((GLFWcursor*)_glfw.cursorListHead);

  for (i = 0; i < _glfw.monitorCount; i++) {
    _GLFWmonitor* monitor = _glfw.monitors[i];
    if (monitor->originalRamp.size)
      _glfwPlatformSetGammaRamp(monitor, &monitor->originalRamp);
    _glfwFreeMonitor(monitor);
  }

  free(_glfw.monitors);
  _glfw.monitors = NULL;
  _glfw.monitorCount = 0;

  free(_glfw.mappings);
  _glfw.mappings = NULL;
  _glfw.mappingCount = 0;

  _glfwTerminateVulkan();
  _glfwPlatformTerminate();

  _glfw.initialized = GLFW_FALSE;

  while (_glfw.errorListHead) {
    _GLFWerror* error = _glfw.errorListHead;
    _glfw.errorListHead = error->next;
    free(error);
  }

  _glfwPlatformDestroyTls(&_glfw.contextSlot);
  _glfwPlatformDestroyTls(&_glfw.errorSlot);
  _glfwPlatformDestroyMutex(&_glfw.errorLock);

  memset(&_glfw, 0, sizeof(_glfw));
}

//////////////////////////////////////////////////////////////////////////
//////                       GLFW internal API                      //////
//////////////////////////////////////////////////////////////////////////

char* _glfw_strdup(const char* source) {
  const size_t length = strlen(source);
  char* result = calloc(length + 1, 1);
  strcpy(result, source);
  return result;
}

float _glfw_fminf(float a, float b) {
  if (a != a)
    return b;
  else if (b != b)
    return a;
  else if (a < b)
    return a;
  else
    return b;
}

float _glfw_fmaxf(float a, float b) {
  if (a != a)
    return b;
  else if (b != b)
    return a;
  else if (a > b)
    return a;
  else
    return b;
}

//////////////////////////////////////////////////////////////////////////
//////                         GLFW event API                       //////
//////////////////////////////////////////////////////////////////////////

// Notifies shared code of an error
//
void _glfwInputError(int code, const char* format, ...) {
  _GLFWerror* error;
  char description[_GLFW_MESSAGE_SIZE];

  if (format) {
    va_list vl;

    va_start(vl, format);
    vsnprintf(description, sizeof(description), format, vl);
    va_end(vl);

    description[sizeof(description) - 1] = '\0';
  } else {
    if (code == GLFW_NOT_INITIALIZED)
      strcpy(description, "The GLFW library is not initialized");
    else if (code == GLFW_NO_CURRENT_CONTEXT)
      strcpy(description, "There is no current context");
    else if (code == GLFW_INVALID_ENUM)
      strcpy(description, "Invalid argument for enum parameter");
    else if (code == GLFW_INVALID_VALUE)
      strcpy(description, "Invalid value for parameter");
    else if (code == GLFW_OUT_OF_MEMORY)
      strcpy(description, "Out of memory");
    else if (code == GLFW_API_UNAVAILABLE)
      strcpy(description, "The requested API is unavailable");
    else if (code == GLFW_VERSION_UNAVAILABLE)
      strcpy(description, "The requested API version is unavailable");
    else if (code == GLFW_PLATFORM_ERROR)
      strcpy(description, "A platform-specific error occurred");
    else if (code == GLFW_FORMAT_UNAVAILABLE)
      strcpy(description, "The requested format is unavailable");
    else if (code == GLFW_NO_WINDOW_CONTEXT)
      strcpy(description, "The specified window has no context");
    else
      strcpy(description, "ERROR: UNKNOWN GLFW ERROR");
  }

  if (_glfw.initialized) {
    error = _glfwPlatformGetTls(&_glfw.errorSlot);
    if (!error) {
      error = calloc(1, sizeof(_GLFWerror));
      _glfwPlatformSetTls(&_glfw.errorSlot, error);
      _glfwPlatformLockMutex(&_glfw.errorLock);
      error->next = _glfw.errorListHead;
      _glfw.errorListHead = error;
      _glfwPlatformUnlockMutex(&_glfw.errorLock);
    }
  } else
    error = &_glfwMainThreadError;

  error->code = code;
  strcpy(error->description, description);

  if (_glfwErrorCallback)
    _glfwErrorCallback(code, description);
}

//////////////////////////////////////////////////////////////////////////
//////                        GLFW public API                       //////
//////////////////////////////////////////////////////////////////////////

GLFWAPI int glfwInit(void) {
  if (_glfw.initialized)
    return GLFW_TRUE;

  memset(&_glfw, 0, sizeof(_glfw));
  _glfw.hints.init = _glfwInitHints;

  if (!_glfwPlatformInit()) {
    terminate();
    return GLFW_FALSE;
  }

  if (!_glfwPlatformCreateMutex(&_glfw.errorLock) ||
      !_glfwPlatformCreateTls(&_glfw.errorSlot) ||
      !_glfwPlatformCreateTls(&_glfw.contextSlot)) {
    terminate();
    return GLFW_FALSE;
  }

  _glfwPlatformSetTls(&_glfw.errorSlot, &_glfwMainThreadError);

  _glfw.initialized = GLFW_TRUE;
  _glfw.timer.offset = _glfwPlatformGetTimerValue();

  glfwDefaultWindowHints();

  {
    int i;

    for (i = 0; _glfwDefaultMappings[i]; i++) {
      if (!glfwUpdateGamepadMappings(_glfwDefaultMappings[i])) {
        terminate();
        return GLFW_FALSE;
      }
    }
  }

  return GLFW_TRUE;
}

GLFWAPI void glfwTerminate(void) {
  if (!_glfw.initialized)
    return;

  terminate();
}

GLFWAPI void glfwInitHint(int hint, int value) {
  switch (hint) {
    case GLFW_JOYSTICK_HAT_BUTTONS:
      _glfwInitHints.hatButtons = value;
      return;
    case GLFW_COCOA_CHDIR_RESOURCES:
      _glfwInitHints.ns.chdir = value;
      return;
    case GLFW_COCOA_MENUBAR:
      _glfwInitHints.ns.menubar = value;
      return;
  }

  _glfwInputError(GLFW_INVALID_ENUM,
                  "Invalid init hint 0x%08X",
                  hint);
}

GLFWAPI void glfwGetVersion(int* major, int* minor, int* rev) {
  if (major != NULL)
    *major = GLFW_VERSION_MAJOR;
  if (minor != NULL)
    *minor = GLFW_VERSION_MINOR;
  if (rev != NULL)
    *rev = GLFW_VERSION_REVISION;
}

GLFWAPI const char* glfwGetVersionString(void) {
  return _glfwPlatformGetVersionString();
}

GLFWAPI int glfwGetError(const char** description) {
  _GLFWerror* error;
  int code = GLFW_NO_ERROR;

  if (description)
    *description = NULL;

  if (_glfw.initialized)
    error = _glfwPlatformGetTls(&_glfw.errorSlot);
  else
    error = &_glfwMainThreadError;

  if (error) {
    code = error->code;
    error->code = GLFW_NO_ERROR;
    if (description && code)
      *description = error->description;
  }

  return code;
}

GLFWAPI GLFWerrorfun glfwSetErrorCallback(GLFWerrorfun cbfun) {
  _GLFW_SWAP_POINTERS(_glfwErrorCallback, cbfun);
  return cbfun;
}
